plugin command


plugin command args
  • command = load or unload or list or clear

  • args = list of arguments for a particular plugin command

    load file = load plugin(s) from shared object in file
    unload style name = unload plugin name of style style
        style = pair or bond or angle or dihedral or improper or kspace or compute or fix or region or command
    list = print a list of currently loaded plugins
    clear = unload all currently loaded plugins


plugin load morse2plugin.so
plugin unload pair morse2/omp
plugin unload command hello
plugin list
plugin clear


The plugin command allows to load (and unload) additional styles and commands into a LAMMPS binary from so-called dynamic shared object (DSO) files. This enables to add new functionality to an existing LAMMPS binary without having to recompile and link the entire executable.

The load command will load and initialize all plugins contained in the plugin DSO with the given filename. A message with information the plugin style and name and more will be printed. Individual DSO files may contain multiple plugins. More details about how to write and compile the plugin DSO is given in programmer’s guide part of the manual under Writing plugins.

The unload command will remove the given style or the given name from the list of available styles. If the plugin style is currently in use, that style instance will be deleted.

The list command will print a list of the loaded plugins and their styles and names.

The clear command will unload all currently loaded plugins.

Automatic loading of plugins

New in version 4May2022.

When the environment variable LAMMPS_PLUGIN_PATH is set, then LAMMPS will search the directory (or directories) listed in this path for files with names that end in plugin.so (e.g. helloplugin.so) and will try to load the contained plugins automatically at start-up.


The plugin command is part of the PLUGIN package. It is only enabled if LAMMPS was built with that package. See the Build package page for more info.

If plugins access functions or classes from a package, LAMMPS must have been compiled with that package included.

Plugins are dependent on the LAMMPS binary interface (ABI) and particularly the MPI library used. So they are not guaranteed to work when the plugin was compiled with a different MPI library or different compilation settings or a different LAMMPS version. There are no checks, so if there is a mismatch the plugin object will either not load or data corruption and crashes may happen.